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Aplysia californica (The California Sea Hare)
Behold Aplysia californica–an extremely large sea slug which grazes on red algae along the California coast. The mollusk is rarely found at depths deeper than 20 meters. It grows to seventy-five cm (thirty inches) in length and weighs a whopping 7kg (15.4 lbs). Aplysia californica belongs to a family of sea slugs known as the sea hares –so called because the two rhinophores (smelling organs) atop the creatures’ heads are fancifully said to resemble a rabbit’s ears.
Aplysia californica (photo by Chris Nelson)
Although this Pacific gastropod is interesting in its own right, the slug is of greatest importance to humankind as a research animal (like the regenerating axolotl). Aplysia has only 20,000 neuron cells–as opposed to a human brain which contains between ten and a hundred billion–and the slug’s neurons are extremely large. This allows neuroscientists to easily observe and assess physiological and molecular changes which take place in the cells when the slug learns something. Aplysia research is thus at the cutting edge of neuroscience. Nearly everything we know about the molecular basis of memory and learning started out as research with the humble gastropod.
A Cartoon of a Sea Hare Learning
A news piece on CNN today featured Dr. Eric Kandel of Columbia University who won the 2000 Nobel Prize in Medicine & Physiology for neural research (mainly on these slugs) and made immense headway on what is probably the great cellular biology mystery of our time. It is a pleasure to see a science article on CNN online but it was also somewhat dismaying to see how many comments were basically “why are we wasting money on studying slugs?” In case it is not self-evident why we are trying to discover the fundamental molecular mechanisms of memory and cognition, here is a brief and not-at-all comprehensive list.
Understanding these underlying biological processes would probably help us find therapy for neuro-degenerative disorders (such as Parkinson’s disease, multiple sclerosis, and Alzheimer’s disease). It might also allow us to comprehend a number of psychiatric conditions, such as schizophrenia and depression. At some point in the future, understanding the molecular basis of memories and thoughts might also allow for the engineering of some sort of bioimplant for the nervous system. You could learn Sanscrit by popping a chip in your head or record your nightmares via wire! Beyond such science fiction concepts, knowing about how the brain works is an end into itself—understanding the most complicated known structure in the universe is a necessary step to building structures of greater complexity.
Although perhaps the politically polemicized commenters who object to studying the sea hare actually reject the creature’s sex life–which is indeed somewhat at odds with traditional notions of romance and propriety.
Like all sea hares, Aplysia californica is a hermaphrodite with both male and female reproductive organs. Because of its physiology it can (and does!) use both sets of organs simultaneously during mating. Multiple Aplysia have been known to form chains of more than 20 animals (somewhat like pop beads) where each animal simultaneously acts as a male and female at the same time with its fore and aft partners. Copulation lasts for many hours (or sometimes for days). One can see how the creatures’ amorous predilections might not sit well with puritans and fundamentalists, however for providing a window into molecular neurophysiology we owe this gentle sea slug a big round of thanks.
“Take a bow! Hmm, somebody teach the slug to bow.”
The coat of arms of Pope Benedict XVI
So does everybody remember Pope Benedict XVI, the German guy who was pope until last month? While I was doing research on Papal tiaras, I happened to come across his personal coat of arms. Holy smokes! Tiaras will have to wait—check out this puppy! Not only does it feature a number of ferrebeekeeper themes–mollusks, mammals, and crowns—it is ridiculously gothic and insanely colorful to boot. The coat of arms features a moor’s head wearing a crown (and how is that an appropriate thing in the modern world?), a bear wearing a backpack (!), and a large scallop shell. The scallop shell is an allusion to pilgrimages and also an allegorical story about Saint Augustine walking on the beach and having an epiphany about divinit. The moor’s head is a traditional symbol of medieval German nobility (as an allusion to beheaded Moorish foes and to suzerainty over Africa): this particular example is apparently the “Moor of Freising” from the coat of arms of the Archdiocese of Munich and Freising. The bear with the backpack is “the bear of St. Corbinian” but I have no idea what he is doing. Maybe he is going to grade school?
This papal coat of arms is unusual in that it is surmounted by a bishop’s miter instead of the traditional three-tiered papal tiera (a symbol of kingship which the papacy has been phasing out, but more about that in another post). The truly important element is there however—the fancy gothic keys of Saint Peter which (according to the Catholic Church) grant access to heaven. Now if only there were a catfish… Speaking of which, below, as a special bonus, I have included the coat of arms of the infamous Urban VIII (who poisoned the birds in the papal garden because their singing disturbed his plotting) which includes the Barberini bees, and the coat of arms of the futile and immoral Pious VI, which shows a weird boy throwing up on a lily.
Coat of Arms of Urban VIII
Coat of Arms of Pious VI
The Dead Christ with Angels (Édouard Manet, 1864, oil on canvas)
Here is one of my favorite disturbing religious paintings. The work was completed in 1864 by the not-easily-classified 19th century French master Édouard Manet. At first glimpse the canvas seems like a conventional devotional painting of Christ just after he has been crucified and laid out in Joseph of Arimathea’s tomb, but, upon closer examination the multifold unsettling elements of the painting become manifest. The figures are painted in Manet’s trademark front-lit style which flattens the figures out and gives them a hint of monstrous unearthliness. This is particularly problematic since we are located at Jesus’ feet and his body is already foreshortened. The effect is of an ill-shaped Jesus with dwarf’s legs looming above us. Also, from his half-closed eyes it is unclear whether Christ is dead or not. Is he artlessly deceased with his eyes partially opened? Has he been resurrected already but is somehow still woozy? Are the angels resurrecting him? Here we get to the biggest problem of the painting: when is this happening? This scene is certainly not in the gospels (at least I don’t remember any episodes where weird angels with cobalt and ash wings move Jesus around like a prop). Did Manet just make up his own disquieting interpretation of the fundamental mystery at the heart of Christianity? It certainly seems like it! In the foreground of the work, empty snail shells further suggest that we have misunderstood the meaning. An adder slithers out from beneath a rock as if to suggest the poison in our doubts. Painting this kind of problematic religious work did not win Manet any friends in the middle of the nineteenth century, however it is unquestionably a magnificent painting about faith…and about doubt.
Colorful Land Snails (artist’s conception)
There are all sorts of snails in my Brooklyn garden which range in color from, well, from medium brown to dark brown. I guess the local mollusks don’t make for a very exciting rainbow–so today we move to the West Indies in search of the most vibrant land snails we can find. There are numerous lovely air-breathing snails throughout (and around) the Caribbean which can be found in a variety of eye-popping colors, but two particular species outshine the others in terms of brilliant red, yellow, black and orange swirls. These are the Cuban land snail (Polymita picta) and the Candy Stripe land Snail (Liguus virgineus) of Hispaniola.
Polymitas picta
Polymita picta lives throughout Cuba where it eats the algae, mold, and lichen from subtropical trees and shrubs. The single species of snails appear in a dazzling array of spiral color patterns.
Polymita picta color variation (Harvard Museum)
Liguus virgineus lives only on Hispaniola (the large island which includes Haiti & the Dominican Republic). Unlike the Cuban land snail, Liguus virgineus specimens are somewhat more homogenous in color and pattern. The Liguus genus however is broadly successful around the Caribbean and Gulf coast and the different species have different patterns (even though they are similar tree snails with similar habitats).
Liguus virginus
Map of Liguus Species
Sadly, both of these snails are at risk because of their brilliant color. The lovely bright colors have proven irresistibly attractive to the world’s most rapacious predator. Humans use the shells as jewelry or collectibles which has led to both species being over-harvested for collectors.
Please Don’t Go (Maria Tomasula, 2010, oil on panel)
Maria Tomasula is a contemporary artist who paints strange collections of beautiful items coalescing into miniature glowing geometric systems (usually against an empty black outer space backdrop). Dew, flowers, and fruit are the most frequent items in these compositions, but sculptures, amphibians, skulls, mollusks, weapons, and disembodied organs (among other things) also find their way into these little microcosms.
Ground of Being (Maria Tomasula, 2010, oil on panel)
Tomasula paints the shining or dewy objects which make up her still life works with finicky photorealism, yet the abstract structure of the works takes these images towards mathematical abstraction. Her delightful little paintings give us the aesthetics of the natural world as viewed through a dark melting kaleidoscope.
Intercession (Maria Tomasula, 2007, oil on panel)
Tomasula has a particular flair for teasing humankind’s magpie-like fascination with shininess and bright colors. From across the gallery, her works beguile the viewer closer and closer. Only when one is next to them does one notice the carnivorous pitcher plants and bird skulls among the velvet, petals, and jewels. However the dark imagery does not outshine the sensuous appeal of these fastidious spirals, loops, and curtains. Tomasula invites us to reach into the dark fractal pattern of beauty to grab the waxy flowers, the moist fruits, the polished gems…if we dare.
Second Nature (Maria Tomasula, 2011, oil on panel)
oil on panel
Melo Pearl
The world’s rarest and most precious pearls do not come from oysters, but instead from very large sea snails of the species Melo melo. Melo melo snails lives in the tropical waters of southeast Asia and range from Burma down around Malysia and up into the Philippines. The snails are huge marine gastropods which live by hunting other smaller snails along the shallow underwater coasts of the warm Southeast Asia seas.
Melo melo snail (Melo melo)
Melo melo is a very lovely snail with a smooth oval shell of orange and cream and with zebra stripes on its soft body. The shell lacks an operculum (the little lid which some snails use to shut their shells) and has a round apex as opposed to the more normal spiral spike. This gives the Melo melo snail’s shell a very aerodynamic lozenge-like appearance (although living specimens look more like alien battlecraft thanks to the large striped feet and funnels). The animals grow to be from 15 to 35 centimeters in length (6 inches to a foot) although larger specimens have been reported. The shell is known locally as the bailer shell because fishermen use the shells to bail out their canoes and small boats.
Melo melo at Birmingham’s National Sea Life Centre (with keeper)
Melo pearls form only rarely on the snails and are due to irritating circumstances unknown to science. No cultivation mechanism exists (which explains the astronomically high prices). A single large melo pearl can sell for hundreds of thousands of dollars or more in Asia. The pearls are usually egg-shaped or oval (although perfectly round specimens are known) and they can measure up to 20-30mm in diameter. Not nacreous (like pearls from oysters & abalones), these valuable objects have a porcelain-like transparent shine. Melo pearls are brown, cream, flesh, and orange (with the brighter orange colors being most valuable).
Melo pearls with Melo melo shell
Apart from the fact that they come from a large orange predatory sea snail, what I like most about melo pearls is the extent to which they evoke the celestial. It is hard not to look at the shining ovals and orbs without thinking of the sun, Mars, Makemake, and Haumea. Rich jewelry aficionados of East Asia, India, and the Gulf states must agree with me. It is difficult to conceive of paying the price of a nice house for a calcium carbon sphere from an irritated/diseased snail, unless such pearl spoke of unearthly beauty and transcendent longing.
Leopard nudibranch / Photo by John Williams
Nudibranchs are gastropod mollusks which live in the oceans worldwide from the polar regions to the tropics. The slugs live in virtually all depths and various species range from the shallow intertidal surf to depths of more than over 700m. Although the majority of nudibranchs are benthic creatures which crawl along the seafloor, some prefer other lives and float upside down under the oceans surface or swim in the water column.
Blue-tipped Nudibranch (Janolus Christus)
Nudibranchs lose their vestigial shell during a larval phase. To protect themselves they rely on toxins or unpleasant tasting chemicals which are advertised with extremely vivid colors. In order to enliven the gray winter months, here is a little parade of lovely nudibranchs. Enjoy!
Nudibranch by Hani Amir
Piggy Back Nudibranch M4 Cava.jpg (33601 bytes)
Piggyback Nudibranch (Risbecia Tryoni) Photo by Laurie Cava
from jaysdaysaway
Nudibranch (Nembrotha kubaryana)
Image: cosmicmache.blogspot.com
Image: cosmicmache.blogspot.com
Hopkin’s Rose Nudibranch (Hopkinsia rosacaea)
Nudibranch by Dermal Denticles
Nembrotha cristata
Ray Troll painting large amoonites for “Night of the Ammonites” exhibit at Seattle’s Burke Museum
One of my favorite living artists is not interested in the fatuous self-absorption and navel gazing which characterizes most contemporary artwork. Instead of falling in love with himself, Ray Troll fell in love with aquatic animals—and his art is a pun-filled paean to the astonishing diversity and complexity of life in Earth’s rivers, lakes, and oceans both in this epoch and in past geological ages. Although Troll’s vibrant biology themed art is humorous and fantastic, it also resonates at a deeper level. Themes of ecological devastation and the broad exploitation of the oceans are unflinchingly explored, as is the true nature of humankind. Troll (correctly) regards people as a sort of terrestrial fish descendant who still have the same aggressive territoriality, unending hunger, and crude drives that propelled our distant piscine forbears. This sounds deterministic and grim until one comprehends the high esteem which Troll holds for fish of all sorts. After looking at the beauty, grace, and power of his fish art, one feels honored to be included in the larger family (along with all the mammals, birds, reptiles, and amphibians which trace their roots back to fish-like tetrapod ancestors).
‘Crusin’ the Fossil Freeway’ by Ray Troll (the artist is visible on the driver’s side)
Troll is a favorite artist because he endeavors to understand paleontology, ecology, and biology and synthesize these extraordinary disciplines with broader human experience. The result is a whimsical and surreal mixture of creatures and concepts from different times and places rubbing elbows as though Hieronymous Bosch were having a happy daydream. Troll is a “popular” artist in that he makes a living by selling books, tee-shirts, and posters rather than swindling billionaire bankers into multi-million dollar single purchases, so you should check out his website. In keeping with the themes of Ferrebeekeeper, I have added a small gallery of his mollusk and catfish themed artwork (although such creatures are only featured in some of his paintings and drawings). Unfortunately the online sample images are rather small. If you want to see full resolution images you will have to buy his books and artwork (which is a worthwhile thing to do).
“The Encante”, (Ray Troll, 2004, colored pencil on paper, 11” x 30”)
The Encante is a paradisiacal underwater realm where shapeshifting river dolphins lure humans. The aquatic creatures are able to be themselves in this realm of magic and dance. Not only does Troll’s work feature the beauty of the Amazon and the otherworldly magical river dolphins, there are also a host of amazing catfish, including several armored catfish, and a giant bottomfeeder which has apparently developed an unfortunate taste for human flesh.
Got Ink? (Ray Troll)
Octopi Wall Street (Ray Troll)
Here are a handful of Troll’s pun-themed tee-shirt drawings involving amazing cephalopods. I like to imagine the populist octopus in battle with the fearsome vampire squid which is so emblematic of Goldman Sachs.
Night of the Ammonites (Ray Troll)
Finally, here is a naturalistic portrayal of how the ancient ammonites most likely came together to spawn on moonlit nights of the Paleozoic (such behavior is characteristic of the squids and cuttlefish alive today). The long-extinct cephalopods are portrayed with life and personality as though their quest to exist has immediate relevance to us today. Indeed–that might is Troll’s overarching artistic and philosophical point: life is a vividly complex web of relationships which knit together in the past, present, and the future.
A School of Humboldt Squid
The world is ever changing. Some organisms are incapable of changing their habitat or behavior to adapt to this mutability, whereas other animals are always doing unexpected things. Among the latter are Humboldt squid (Dosidicus gigas) large aggressive cephalopods which are always popping up in unexpected locations. These squid usually live in the open ocean at water depths between 200 & 700 m (660 to 2,300 feet) however they are apparently capable of swimming higher or lower. Similarly although they used to live predominantly in the Humboldt Current (which runs from Tierra del Fuego up through Central America), it seems they are now migrating north. Great schools of Humboldt squid were spotted this week off the coasts of Los Angeles. Lately they have been reported as far north as Seattle, British Columbia, and even Alaska. Scientists speculate that the squid are moving north in response to overfishing and climate change. It also seems that the acidification of the ocean is changing their metabolism and driving them to more shallow water (which allows for greater oxygen uptake).
A Humboldt Squid with a Diver
Humboldt squid can grow up to 1.5 meters (4.9 feet) in length and weigh as much as 50 kilograms (100 pounds). They have eight swimming/grasping arms and two long lightning-fast hunting arms lined with toothed suckers. The squid assemble in great schools of up to 1,200 individuals. They communicate through bioluminescence and rapidly changing body color. They are capable of group hunting—which makes a large school into a 50 ton super monster with ten thousand arms. The squid feed opportunistically on everything they can catch including fish, crustaceans, and other cephalopods (sometimes including each other). Oh, also they have large razor sharp beaks and are surprisingly intelligent. Humboldt squid have been known to attack divers (which can be a problem because of their size, spped, and sharp toothed suction cups) on the other hand they are said to be tasty is prepared correctly.
A Black Smoker Geothermal Vent
The African Plate and the Indo-Australian Plate meet together deep beneath the surface of the Indian Ocean in a long line of tectonic divergence known as the Central Indian Ridge (CIR). As new seafloor is created hydrothermal vents pour out molten hot fluids rich with minerals and an alien landscape is formed. The hot minerals precipitate to form high cylindrical chimneys called smokers and strange communities of life form along these structures. This ecosystem is entirely based upon chemosynthetic archaea (ancient one-celled life forms which take energy directly from the oxidation of inorganic compounds). Great communities of eyeless shrimp, giant tubeworms, and annelids support themselves on the archaea. Among the strange creatures is a very weird gastropod mollusk, the scaly-foot snail (Crysomallon squamiferum), which is different from every other mollusk (and indeed every other animal) because of the material it uses for its bizarre scale-mail armor.
The Scaly Foot Gastropod (Crysomallon squamiferum)
The scaly foot gastropod has an armored foot which is covered in little scales made of iron sulfides. Additionally the deep-sea snail has a triple layer shell. The outermost shell layer is composed of iron sulfides, the middle is a thick protein coat, and the inner shell layer is composed of aragonite (a calcium carbonate).
I wish I could tell you more about the habits of this snail but since it is found in super heated water at the bottom of the Indian Ocean, it has not been extensively studied. However, The US military is interested in the creature as a possible inspiration for next generation composite military armor so maybe we will all learn more about the scaly foot snail.
Detail of the Foot Armor of Crysomallon squamiferum
